PRODUCT INFORMATION 05/01

Transcription

1 RODCT INFORMATION 05/01 BATTERY HEAT DISSIATION DRING FLOAT OERATION, RECHARGE AND DISCHARGE Float operation The heat dissipation power during the operation mode can be calculated by the following equation for one cell: 2 ( ) I + R I = gas i ac - is defined as (normally for flooded BAE batteries at 2,23V and for BAE valve regulated batteries at 2,25V) gas - is a constant value (water decomposing ) given for all flooded batteries 1,48V, assuming, that all the current is used for water decomposition. For valve regulated batteries is this value equivalent to zero, assuming that all the current is used for internal recombination. I - is defined as current. At normal conditions (20 C and 2,23V for flooded batteries and 2,25V for valve regulated batteries) the current is nearly 15mA / 100 Ah of nominal capacity for valve regulated batteries and 25 ma / 100 Ah for flooded batteries. (For higher temperatures and s please see the dependence at figure 1.) Float char current per 100 Ah BAE OzV / OGiV BAE OzS / OGi ma 25 ma During life time the current of the vented (flooded) batteries increases by a factor of 1,5 to 2, caused by antimony poisoning of the batteries. R - is the internal resistance of the cell. The internal resistance depends on the plate design of i the cells and the capacity. I - is defined as effective ripple current of the charging unit. According to EN the ac maximum allowed permanent ripple current is 5A per 100 Ah. Example 6 OzS 300 cell (flooded cell with tubular plate technology): = ( 2,23 V 1,48 V) 3 25 ma + 0,63 mω ( 3 5 A) 2 = 0,133 W Example 7 OzV 490 cell (valve regulated cell with tubular plate technology): = ( 2,25 V) 4,9 15 ma + 0,51mΩ ( 4,9 5 A) 2 = 0,472 W E N E R G Y F R O M B A T T E R I E S R:\Stationär\roduktinformationen\Englisch\105heat_calculation.doc wrus, m. schiemann

2 BAE Berliner Batterie GmbH RODCT INFORMATION 05/ FLOAT CRRENT as a function of and T 40 C 30 C 20 C 10 C ch ar cu rre nt I [m A] ,2 2,25 2,3 2,35 2,4 2,45 2,5 2,55 2,6 2,65 2,7 2,75 2,8 char figure 1 current as a function of and temperature In accordance with the example 1 calculation, we t following results for the whole product ran of flooded / vented OzS cells: Type C10 I R i Ah ma mω W / cell 4 OzS ,0 0,95 0,133 5 OzS ,5 0,76 0,166 6 OzS ,0 0,63 0,198 5 OzS ,5 0,70 0,280 6 OzS ,0 0,58 0,335 7 OzS ,5 0,50 0,392 6 OzS ,0 0,47 0,536 8 OzS ,0 0,35 0, OzS ,0 0,28 0, OzS ,0 0,23 1, OzS ,0 0,23 1, OzS ,0 0,17 2, OzS ,0 0,14 2, OzS ,0 0,11 3,038 2

3 BAE Berliner Batterie GmbH RODCT INFORMATION 05/01 In accordance with the example 2 calculation, we t following results for the whole product ran of valve regulated SzV60 / SzV 110 and OzV cells: SzV 60 SzV 110 OzV Type C10 I R i Ah ma mω W / cell 2 SzV ,0 1,70 0,102 3 SzV ,0 1,13 0,152 4 SzV ,0 0,85 0,203 5 SzV ,0 0,68 0,254 6 SzV ,0 0,57 0,306 7 SzV ,0 0,49 0,358 8 SzV ,0 0,43 0,410 9 SzV ,0 0,38 0, SzV ,0 0,34 0,509 Type C10 I R i Ah ma mω W / cell 3 SzV ,5 0,93 0,365 4 SzV ,0 0,70 0,487 5 SzV ,5 0,56 0,609 6 SzV ,0 0,47 0,735 7 SzV ,5 0,40 0,853 8 SzV ,0 0,35 0,975 9 SzV ,5 0,31 1, SzV ,0 0,28 1,218 Type C10 I R i Ah ma mω W / cell 4 OzV ,0 1,20 0,188 5 OzV ,5 0,96 0,234 6 OzV ,0 0,80 0,281 5 OzV ,5 0,71 0,336 6 OzV ,0 0,60 0,406 7 OzV ,5 0,51 0,472 6 OzV ,0 0,45 0,608 8 OzV ,0 0,34 0, OzV ,0 0,27 1, OzV ,0 0,23 1, OzV ,0 0,24 1, OzV ,0 0,18 2, OzV ,0 0,14 3, OzV ,0 0,12 3,713 3

4 BAE Berliner Batterie GmbH RODCT INFORMATION 05/01 Dischar operation The heating dissipation during dischar operation depends on the dischar current and the difference between the open-circuit ( 0 = 0,84 + electrolyte gravity) and the actual dischar of the battery. The gravity of the flooded cells were measured during the dischar. For the valve regulated batteries is it possible to assume the same GEL gravity at the end of dischar. The SzV cell types are filled with GEL with a gravity of 1,26 kg/l. The higher GEL gravity shifts a bit the difference ( 0 disch ar ). As equation for the heating calculation this formula is used ( 0 disch ar ) Idisch ar disch arg e = For all calculations a dischar during 1 h is assumed with a final of 1,67 V per cell. As dischar current the current of the project planning data is selected, which includes the differences of the different plate lengths and plate numbers at a plate set. OzS cells: pe r ce ll 2,15 2,10 2,05 1,95 1,90 1,85 1,75 1,70 1,65 1,60 BAE Secura OzS open-circuit, dischar and difference during C1 dischar (168 A dischar current) 6 OzS 300 dischar initial = acid gravity + 0,84 ; mean value = 0,211 V 0, dischar time t [min] 1,20 1,10 1,00 0,90 0,80 0,70 0,60 0,50 0,40 0,30 0,20 0,10 dif fer nc e figure 2 dischar, open-circuit and difference during 1 h dischar of BAE 6 OzS 300 So we can calculate for the heat dissipation power of a 6 OzS 300 cell during 1 h dischar: disch arg e = 0,211 V 168 A = 35,45 W 4

5 BAE Berliner Batterie GmbH RODCT INFORMATION 05/01 Type C10 I C1 dischar Ah A W / cell 4 OzS ,63 5 OzS ,54 6 OzS ,45 5 OzS OzS ,64 7 OzS ,08 6 OzS ,52 8 OzS ,89 10 OzS ,46 12 OzS ,83 12 OzS ,58 16 OzS ,44 20 OzS ,30 24 OzS ,16 OzV cells: pe r ce ll 2,15 2,10 2,05 1,95 1,90 1,85 1,75 1,70 1,65 1,60 BAE Secura OzV open-circuit, dischar and difference during C1 dischar (158 A dischar current) 6 OzV 300 initial = acid gravity (assumed value) + 0,84 dischar ; mean value = 0,184 V 0, dischar time t [min] 1,20 1,10 1,00 0,90 0,80 0,70 0,60 0,50 0,40 0,30 0,20 0,10 dif fer nc e figure 3 dischar, open-circuit and difference during 1 h dischar of BAE 6 OzV 300 5

6 BAE Berliner Batterie GmbH RODCT INFORMATION 05/01 Type C10 I C1 dischar Ah A W / cell 4 OzV ,47 5 OzV ,54 6 OzV ,62 5 OzV ,03 6 OzV ,31 7 OzV ,59 6 OzV ,47 8 OzV ,02 10 OzV ,39 12 OzV ,94 12 OzV ,40 16 OzV ,66 20 OzV ,73 24 OzV ,98 SZV 60 pe r ce ll 2,15 2,10 2,05 1,95 1,90 1,85 1,75 1,70 1,65 1,60 BAE Secura SzV 60 open-circuit, dischar and difference during C1 dischar (115 A dischar current) 3 SzV 180 initial = acid gravity (assumed value) + 0,84 dischar ; mean value = 0,185 V 0, dischar time t [min] 1,20 1,10 1,00 0,90 0,80 0,70 0,60 0,50 0,40 0,30 0,20 0,10 dif fer nc e figure 4 dischar, open.circuit and difference during 1 h dischar of BAE 3 SzV 180 6

7 BAE Berliner Batterie GmbH RODCT INFORMATION 05/01 Type C10 I C1 dischar Ah A W / cell 2 SzV ,2 14,28 3 SzV ,46 4 SzV ,49 5 SzV ,71 6 SzV ,92 7 SzV ,95 8 SzV ,17 9 SzV ,20 10 SzV ,41 SzV 110 pe r ce ll 2,15 2,10 2,05 1,95 1,90 1,85 1,75 1,70 1,65 1,60 BAE Secura SzV 110 open-circuit, dischar and difference during C1 dischar (536 A dischar current) 8 SzV 880 initial = acid gravity (assumed value) + 0,84 dischar ; mean value = 0,266 V 0, dischar time t [min] 1,20 1,10 1,00 0,90 0,80 0,70 0,60 0,50 0,40 0,30 0,20 0,10 dif fer nc e figure 5 dischar, open-circuit and difference during 1 h dischar of BAE 8 SzV 880 7

8 BAE Berliner Batterie GmbH RODCT INFORMATION 05/01 Type C10 I C1 dischar Ah A W / cell 3 SzV ,15 4 SzV ,37 5 SzV ,33 6 SzV ,29 7 SzV ,52 8 SzV ,59 9 SzV ,67 10 SzV ,74 8

9 BAE Berliner Batterie GmbH RODCT INFORMATION 05/01 Rechar operation The calculation is nearly the same like at dischar operation. The heat dissipation is now a product of the mean value of rechar current and the difference between the open-circuit and the rechar. The heat dissipation due to the ripple current is neglected, because it is less than 5% of the rechar current effect. All calculation examples are carried out for a initial rechar current of 1,5 x I10 (nominal current) and a boost char of 2,4 V. The rechar time for the calculation is limited to a charging factor of 1,0. The avera current during the boost char operation can be assumed as 90 % of the initial current for all calculations. During the rechar there is nearly no difference between the rechar behaviour of OzS, OzV and SzV 60 and SzV110 cells. ( recharg e 0 ) I recharg e recharg e = Example: Rechar during 315 min (5,25 h) of BAE 6 OzS 300 cell, initial charging current 45 A (avera charging current 40,3 A = 89,5 % ): pe r ce ll 2,50 2,45 2,40 2,35 2,30 2,25 2,15 2,10 2,05 1,95 1,90 1,85 1,75 BAE Secura OzS open-circuit, rechar and during I rechar (inital diff current 45 A / 1,5 x 10 I; avera rechar current 40,3 A = 0,9 x 1,5 x I10) rechar ; mean value = 0,170 V Open-circuit = acid gravity + 0,84 0, dischar time t [min] figure 6 - rechar, natural and difference of BAE 6 OzS 300 Heat dissipation power during rechar of the cell: resch arg e = 0,170 V 40,3 A = 6,851 W 1,00 0,80 0,60 0,40 0,20 9

10 BAE Berliner Batterie GmbH RODCT INFORMATION 05/01 OzS cells: Type C10 I C10 I 1,5 x C10 (90 %) rechar Ah A A W / cell 4 OzS ,00 4,62 5 OzS ,75 5,77 6 OzS ,50 6,93 5 OzS ,25 8,08 6 OzS ,70 9,70 7 OzS ,15 11,31 6 OzS ,00 13,85 8 OzS ,00 18,47 10 OzS ,00 23,09 12 OzS ,70 12 OzS ,50 34,63 16 OzS ,00 46,17 20 OzS ,50 57,71 24 OzS ,00 69,26 Example: rechar during 345 min (5,75 h) of BAE 6 OzV 300 cell, initial charging current 45 A (avera charging current 42 A = 93 % ): pe r ce ll 2,50 2,45 2,40 2,35 2,30 2,25 2,15 2,10 2,05 1,95 1,90 1,85 1,75 BAE Secura OzV open-circuit, rechar and during I rechar (inital diff current 45 A / 1,5 x 10 I; averan rechar current 42 A = 0,93 x 1,5 x I10) rechar open-circuit = acid gravity (assumed) + ; mean value = 0,173 V dischar time t [min] figure 7 - rechar, open-circuit and difference of BAE 6 OzV 300 Rejected continues power during rechar of the cell: rech arg e = 0,173 V 42 A = 7,266 W 3,00 2,80 2,60 2,40 1,60 1,40 1,20 1,00 0,80 0,60 0,40 0,20 0,00 10

11 BAE Berliner Batterie GmbH RODCT INFORMATION 05/01 SzV 60 SzV 110 OzV Type C10 I C10 I 1,5 x C10 (90 %) rechar Ah A A W / cell 2 SzV ,20 2,80 3 SzV ,30 4,20 4 SzV ,40 5,61 5 SzV ,50 7,01 6 SzV ,60 8,41 7 SzV ,70 9,81 8 SzV ,80 11,21 9 SzV ,90 12,61 10 SzV ,00 14,01 Type C10 I C10 I 1,5 x C10 (90 %) rechar Ah A A W / cell 3 SzV ,55 7,71 4 SzV ,40 10,28 5 SzV ,25 12,85 6 SzV ,10 15,41 7 SzV ,95 17,98 8 SzV ,80 20,55 9 SzV ,65 23,12 10 SzV ,50 25,69 Type C10 I C10 I 1,5 x C10 (90 %) rechar Ah A A W / cell 4 OzV ,00 46,71 5 OzV ,50 58,39 6 OzV ,00 70,07 5 OzV ,50 81,74 6 OzV ,00 98,09 7 OzV ,50 114,44 6 OzV ,00 140,13 8 OzV ,00 186,84 10 OzV ,00 233,55 12 OzV ,00 280,26 12 OzV ,00 350,33 16 OzV ,00 467,10 20 OzV ,00 583,88 24 OzV ,00 700,65 11

12 BAE Berliner Batterie GmbH RODCT INFORMATION 05/01 All the calculation are carried out only for one cell. For the whole battery the continues power should be multiply by the number of cell of the battery. M. Schiemann 12